If you want a good study that doesn’t cherry pick data the way Lambert
likes to do,

The cherry-picking is Shawn’s. How come you’re not objecting to his
Vermont vs DC comparison?

read the study by Jeff Miron entitled “Violence, Guns, and Drugs: A Cross-Country Analysis”
Miron’s work is the most comprehensive that I know of that tries to
account for different factors across countries and he finds evidence
that gun control is either significantly positively or insignificantly
positively related to more crime. I would love to see Lambert try to
explain away these results or show one study that has done as much
across countries.

Be happy to oblige. The measure of gun control that Miron uses is a 3
point scale:
(0) – no controls
(1) – some controls
(2) – complete ban

On this scale, the US and the UK have exactly the same amount of gun
control. Even if his study tells us something about gun control, it
doesn’t tell us whether US or UK style control is preferable.

The ICVS measures gun ownership across several nations and shows that
more guns are associated with more homicides and more firearm
homicides.

Mark Duggan has looked at gun ownership at the county level in the US
and found that, again, more guns are associated with more homicides.

Here is Duggan’s article:
(this might not work if your library doesn’t have a subscription to
the Journal of Political Economy)